sush: Maybe you have a file called edge.m on your path that is hiding the toolbox edge function. What is the output of the command "which edge"? If the result isn't in the Image Processing Toolbox, you could try renaming your edge.m file.
farah: Yes, you can use another set of images. You'll see that the images are read from disk at the start of the demo, and you can change those lines to read different images. However, it will be better in the end to write your own code to call correlCorresp rather than relying on the demo. If you are not sure how to proceed, you may need to work through "Getting Started with Matlab" in the documentation.
MD JAYED Hussan: The corresponding coordinates are held in the corresps property of a correlCorresp object, after a call to the findCorresps method. You can see how the vectors are computed by inspecting the code for correspDisplay. It's all in the documentation, by the way.